Before diving into the assembly of your brain game, we should go over the procedure for through-hole soldering.

Why is it called through-hole, you ask? You'll notice the circuit board has a bunch of holes in it, each with a copper trace on the underside of the board. The leads of each component are fed through these holes (hence through-hole) and soldered to the copper trace.

Through-hole soldering is generally regarded as the simplest form of soldering.